Description
The surface of the metal before processing is covered with small scratches, and if these small scratches continue to receive driving torque, stress concentration will occur, cracks will occur, and damage and seizure will occur. By removing burrs from each part and polishing it, the origin of cracks is eliminated and damage is prevented. In addition, the grease used for the joints can withstand high-load driving such as circuit driving by using grease with high heat resistance and extreme pressure. A drive shaft that improves durability and moves smoothly with little resistance is the key to creating a pleasant car.